April 5, 2011

Green Algae Lives In Partnership With Salamander Embryos

The team from Dalhousie University in Halifax, Canada was the first to document a case of a plant living in partnership with a vertebrate.

The researchers think that the salamanders might inherit the algae from their parents.

The study is published in Proceedings of the National Academy of Sciences.

It was already known that green algae lived inside the eggs of the spotted salamander species, which is common in North America.

Salamanders lay their translucent eggs in ponds, where they are suspended near the surface. This makes an ideal, sunny and protected environment for the algae.

"The eggs actually look green because the algae is inside the egg capsules," Dr Ryan Kerney of Dalhousie University, who led the research, told BBC.

"The algae inside the egg capsules provide oxygen to the embryo and the algae gets waste from the embryo [which is rich in the nitrogen the plant needs]."

Scientists did not understand how the algae got into the egg.

The researchers were able to see the algal pigments "shine" when they were illuminated with light of a certain wavelength.

Many scientists did not think that plants could live inside the cells of vertebrates. The group of complex animals have highly specialized immune systems, which should not let these foreign organisms live in our cells.

"We also found algae DNA in the reproductive organs of the adult salamanders," Dr Kerney told BBC, "so it seems possible that it is being inherited.

"We call that vertical transmission, but there is probably a mixture of this and the algae being absorbed from the environment."

Dr Kerney added: "So many new discoveries in biology comes from research in the tropics.

"I think this shows that it's worthwhile to look at our local species. They can still surprise us."